Abstract: This invention comprises an adsorption process for the removal of at least N2O from a feed gas stream that also contains nitrogen and possibly CO2 and water. In the process the feed stream is passed over adsorbents to remove impurities such as CO2 and water, then over an additional adsorbent having a high N2O/N2 separation factor. In a preferred mode the invention is an air prepurification process for the removal of impurities from air prior to cryogenic separation of air. An apparatus for operating the process is also disclosed.

Abstract: For PSA or TSA prepurifiers, the temperature rise on adsorption is particularly troublesome when the temperature rise reaches the end of the bed at the end of the adsorption step. This results in an increase in the CO2 and N2O concentration at the end of the cycle. Addition of a regenerator in the middle of the adsorption layer will reduce the temperature rise at the end of the bed and thus enhance the performance of the bed.

Abstract: This invention relates to an apparatus and process for the removal of impurities, such as propane, from gas streams. A preferred apparatus and process thereof uses a multilayered adsorbent bed wherein a discrete layer of silicalite adsorbent is used to remove propane and other impurities from air.